SELECT 
  1 
FROM 
  cscart_ec_print_temp_designs 
WHERE 
  session_id = '8M2A-BNGW-4CV0-6SMW-01ET-TGP1-CX24-E6K5' 
  AND product_id = 23 
  AND expires_at > 1770174957 
  AND confirmed = 'Y' 
LIMIT 
  1

Query time 0.00049

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}